| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [am/are] [vb pp] [prep] a [noun] | 1977 |
|
| 2 | [be] [vb pp] [prep] a period | 166 |
|
| 3 | [am/are] [vb pp] [prep] [art] period | 15 |
|
| 4 | [am/are] [vb pp] [prep] [art] period | 15 |
|
| 5 | [am/are] [verb] [prep] a period | 12 |
|
| 6 | [am/are] [vb pp] [prep] a period | 8 |
|
| 7 | [am/are] [vb pp] [prep] a period | 8 |
|
